Recent epidemiological and other survey data suggest that a significant number of pregnant women and those in child bearing age abuse illicit drugs, in particular cocaine, with serious consequences such as premature delivery, low birth weight infants, high infant morbidity and long term sequelae. Therefore, it is important that these high risk infants are identified soon after birth, and it possible, the type, degree and duration of exposure to drugs, in utero. Currently, the methods used to accomplish this are by maternal self-report or by urine toxicology screen. Studies have shown that these methods do not consistently provide reliable and valid exposure data. A new method has been developed that identifies the drug exposed neonates by analysis of their stools (meconium) for drug metabolites. The test is quantitative, rapid, non invasive and by far, more sensitive than the current tests that are available. Since meconium, unlike urine, is not normally excreted by the fetus in utero, meconium accumulates in the fetus throughout gestation. Thus, further studies on meconium may provide details about the maternal drug such as the amount, timing and duration of her drug abuse. Comprehensive information of this nature are valuable for epidemiological and clinical purposes and are vital to our understanding of the complex relationship between drug use during pregnancy and its effects on the mother and fetus. The objective of this study is to determine whether the concentration of drug metabolites in meconium correlate to the amount, timing and duration of drug use by the mother. To accomplish this, a group of pregnant addicts who attend our maternal high risk clinic will be selected for follow up during pregnancy. The amount, time and duration of drug abuse by these subjects will be monitored throughout gestation by means of in depth interviews and by maternal hair analyses. Neither maternal nor infant urine will be tested for this purpose since these tests mostly reflect the recent use of drugs by the mother. After delivery, meconium that is serially passed by the infant will be analyzed for the metabolites of morphine, cocaine, and cannabinoid, three of the most common drugs of abuse. The individual and cumulative concentrations of each drug metabolite in meconium will be correlated to the maternal drug use as obtained from the interview and hair analysis. This study is designed to develop the potential of meconium drug analysis as a comprehensive diagnostic test. Currently, there is the need for an objective and sensitive test during the newborn period which can measure the type, amount, timing and duration of the infant's exposure to drugs in utero. An assessment of the potential to achieve this with the meconium analysis is proposed.